error.js

'use strict'

const constants = require('../constants')
const formatUtils = require('../formatUtils')
const isEnumerable = require('../isEnumerable')
const lineBuilder = require('../lineBuilder')
const NOOP_RECURSOR = require('../recursorUtils').NOOP_RECURSOR
const object = require('./object')

const UNEQUAL = constants.UNEQUAL

function describe (props) {
  const error = props.value
  return new DescribedErrorValue(Object.assign({
    nameIsEnumerable: isEnumerable(error, 'name'),
    name: error.name,
    messageIsEnumerable: isEnumerable(error, 'message'),
    message: error.message,
  }, props))
}
exports.describe = describe

function deserialize (state, recursor) {
  return new DeserializedErrorValue(state, recursor)
}
exports.deserialize = deserialize

const tag = Symbol('ErrorValue')
exports.tag = tag

class ErrorValue extends object.ObjectValue {
  constructor (props) {
    super(props)
    this.name = props.name
  }

  compare (expected) {
    return this.tag === expected.tag && this.name === expected.name
      ? super.compare(expected)
      : UNEQUAL
  }

  formatShallow (theme, indent) {
    const name = this.name || this.ctor

    let string = name
      ? formatUtils.wrap(theme.error.name, name)
      : formatUtils.wrap(theme.object.stringTag, this.stringTag)
    if (this.ctor && this.ctor !== name) {
      string += ' ' + formatUtils.wrap(theme.error.ctor, this.ctor)
    }
    if (this.stringTag && this.stringTag !== this.ctor && this.name && !this.name.includes(this.stringTag)) {
      string += ' ' + formatUtils.wrap(theme.object.secondaryStringTag, this.stringTag)
    }
    string += ' ' + theme.object.openBracket

    return super.formatShallow(theme, indent).customize({
      finalize (innerLines) {
        return innerLines.isEmpty
          ? lineBuilder.single(string + theme.object.closeBracket)
          : lineBuilder.first(string)
            .concat(innerLines.withFirstPrefixed(indent.increase()).stripFlags())
            .append(lineBuilder.last(indent + theme.object.closeBracket))
      },

      maxDepth () {
        return lineBuilder.single(string + ' ' + theme.maxDepth + ' ' + theme.object.closeBracket)
      },
    })
  }

  serialize () {
    return [this.name, super.serialize()]
  }
}
Object.defineProperty(ErrorValue.prototype, 'tag', { value: tag })

class DescribedErrorValue extends object.DescribedMixin(ErrorValue) {
  constructor (props) {
    super(props)
    this.nameIsEnumerable = props.nameIsEnumerable
    this.messageIsEnumerable = props.messageIsEnumerable
    this.message = props.message
  }

  createPropertyRecursor () {
    const recursor = super.createPropertyRecursor()

    let skipName = this.nameIsEnumerable
    let emitMessage = !this.messageIsEnumerable

    let size = recursor.size
    if (skipName && size > 0) {
      size -= 1
    }
    if (emitMessage) {
      size += 1
    }

    if (size === 0) return NOOP_RECURSOR

    let done = false
    const next = () => {
      if (done) return null

      const property = recursor.next()
      if (property) {
        if (skipName && property.key.value === 'name') {
          skipName = false
          return next()
        }
        return property
      }

      if (emitMessage) {
        emitMessage = false
        return this.describeProperty('message', this.describeAny(this.message))
      }

      done = true
      return null
    }

    return { size, next }
  }
}

class DeserializedErrorValue extends object.DeserializedMixin(ErrorValue) {
  constructor (state, recursor) {
    super(state[1], recursor)
    this.name = state[0]
  }
}